Léon Theremin and The Thing: fear at the heart of power

By Justin Pollard

Published Saturday, September 17, 2016

One of the great joys of inventing something is being able to name it – unless of course no one is meant to know about it. That’s how Léon Theremin ended up the proud inventor of a device called ‘The Thing’.

Léon Theremin was an exceptional electronics engineer by any standards. The founding father of electronic music, he was the creator of the eponymous Theremin (or etherphone as he preferred to call it), the designer of the world’s first drum machine and the inventor of interlaced video. He was an undoubted genius. Yet perhaps his most successful invention had no name at all.

Theremin had already established an interesting career by the time he arrived at a Sharashka, one of the secret research and development laboratories that formed part of the Soviet gulag labour camp system. Having survived the Russian Revolution and subsequent Civil War, he had toured the world with his revolutionary musical instruments before finally settling in New York.

Then in 1938, he simply ‘disappeared’. Some said the Soviets had abducted him, others thought he had fled the country due to ‘irregularities’ in his tax affairs. However, the only people who knew his location were the NKVD – predecessor to the KGB – who had him in custody.

Of course Theremin, like his fellow Sharashka workers Andrei Tupolev and Sergei Korolev, was not your ordinary Stalinist prisoner, and so was put to work on a special project, directing his encyclopaedic knowledge of radio engineering towards espionage devices.

His first success was the Buran eavesdropping system, which bounced a low-power infrared beam off windows to record vibrations produced by voices in the room, thus reconstructing the conversation. This was the precursor of all modern laser microphones.

Yet his greatest achievement was still more secret. On 4 August 1945, a delegation from the Young Pioneer organisation of the Soviet Union presented a beautiful carving of the Great Seal of the United States of America to the US ambassador in Moscow. He was so taken with it that he had it hanging in his official residence. What he didn’t know was that, from that moment, it was transmitting his conversations back to the NKVD.

Now, the Americans weren’t idiots. They were aware that unprompted gifts from Soviet institutions might contain more than they bargained for and they expected attempts to be made to bug the ambassador’s residence in Moscow. Gifts were checked to make sure they weren’t ‘transmitting’ and the rooms were regularly swept for bugs. The Great Seal came up clean every time.

Yet of course it wasn’t. Hidden deep inside the wooden seal was a small electrical device, weighing just over an ounce. It was so secret, so puzzling and so fiendish it was simply called ‘The Thing’.

The Thing had no battery pack and no active electronic components, so bug sweeps never showed it up. It appeared to be a completely dead packet of electronics, but that was Theremin’s genius. This was a passive cavity resonator, a miniature capacitive membrane connected to an antenna to form an electronic listening device. The device only became active when a radio signal of the correct frequency was fired at it, providing it with the power it needed to operate. When people in the room talked, the sound waves caused the membrane to vibrate, changing the capacitance which in turn modulated the radio waves that struck it and were retransmitted by the device itself.

For seven years, The Thing sat on the wall in the Ambassador’s office, with no batteries to change and no active components to give it away. It might still be there now, were it not for a radio operator at the British embassy who suddenly one day found himself listening in to his American colleagues on an open channel. It was just by luck that he happened to be listening on the right frequency when the Soviets were ‘painting’ the Thing with its radio signal.

The Americans were informed and in March 1951 the device was discovered inside the Great Seal. The device was quickly copied by the British and Americans and rapidly installed wherever they might get away with it.

The idea of a passive electronic transmitting device has since taken on a life of its own – we just don’t call them ‘Things’, we call them RFIDs. So next time you’re making a contactless payment, or using an Oystercard, it’s worth remembering that this extraordinary everyday technology owes its existence to the inventor of the Theremin’s spell in a Soviet gulag.